Normally people think the reason for the phenomenon of season is the distance to the sun. However, this is not true. The real reason is the tilt of our earth.
The rotation axis of earth has a 23.5 degree deviation angle. When earth revolves around the sun, the same area receives different energy from the sun. For example, if a place is located on latitude N23.5, it’s summer is in June.
This place is directly shined by the sun, therefor it receives the strongest heat and light energy than any other places. On the contrary, when it’s December, the sunlight shines obliquely thus acquiring less energy. This makes the temperature low and causes winter.
The phenomenon of “long day” and “long dark” are also related to the tilted self-rotational axis of earth. While summer, northern area is exposed to the sun for a much longer period of time. It makes the day much longer than the night. Here is picture that shows how this works.
[img]https://5.share.photo.xuite.net/teach073/15dfd82/9629604/421677278_m.jpg[/img]
